Process and means relating to manufacture of hollow cast bodies



Mam}! 5, 1963 P. BRENNER 3,079,654

NS RELATING TO MANUFACTURE PROCESS AND MEA 0F HOLLOW ,CAST BODIES Filed Aug. 4, 1960 3 Sheets-Sheet 1 1 I20 Fig.4.

- 20 20a I F 2| \Q/x l2b 2 l2d 2e uvmvron Paul Brenner March 5, 1963 P. BRENNER PROCESS AND MEANS RELATING TO MANUFACTURE OF HOLLOW CAST BODIES 3 Sheets-Sheet 2 Filed Aug. 4, 1960 Fig. 6.

uvmvrmz Paul Brenne r BY March 5, 1963 P. BRENNER 3,079,654

PROCESS AND MEANS RELATING TO MANUFACTURE OF HOLLOW CAST BODIES Filed Aug. 4, 1960 5 Sheets-Sheet 3 INVENTOR. Poul Brenner mJ/M United States Patent 37fi54 i atented Mar. 5, 1953 dice 3,079,654 PRQQESS AND INEANS RELATENG T9 MANU- FACTURE 0F HOLLQW CAST BGDIES Paul Brenner, Bad Godesherg, Germany, assignor to Vereinigte Leichtmetall-Werlre, Gesellsehfit mit heschranlrter Haftung, Bonn, Germany Filed Aug. 4, 1960, Ser. No. 47,486 Claims priority, application Germany Aug. 22, 1959 6 Claims. (Cl. 2257.2)

This invention relates to an improved method of and means for manufacturing hollow bodies, particularly bodies formed of light metals, by a continuous casting process. Reference is made to prior US. patent application, Serial No. 704,163, filed December 20, 1957, entitled Method for Manufacturing Semi-Finished Metallic Prodnets, and filed in the name of Walter Roth et al., and to US. patent application, Serial No. 1,075, filed July l, 1960, now Patent Number 3,005,067, issued September 25, 1962, entitled Method and Apparatus for Manufacturing Semi- Pinished Metallic Products, filed in the name of Walter Roth; the latter identified application being a continuationinpart of the former application.

Briefly stated, prior US. patent application, Serial No. 704,103, discloses a method and apparatus for continuou ly casting an ingot of metal or the like while introducing into the molten material of the ingot being cast in a direction longitudinally thereof and at the same speed that the casting of the ingot is taking place, a plurality of heat resistant separating strips or bands which become permanently embedded in the ingot when it solidifies during the casting operation. Said prior application further teaches how the ingot may be hot or cold rolled so as to reduce the ingot to desired thickness, and which determines in part at least the ultimate shape and cell size of the hollow body being manufactured. When using separating strips made of glass cloth, asbestos, or the like, the pressure rolling of the ingot to attenuate the material also serves to crush and reduce to powdery form the separating strips. As a further processing step, said prior application, Serial No. 704,103, teaches how the ingot, or transverse slices or sections cut therefrom, may be expanded to form an integral cast body having multiple cell openings defined by the spaces formerly occupied by the strips or hands of heat resistant material.

Said prior application, Serial No. 1,075, discloses various means for mounting, tensioning and guiding the separating strips or hands before and during the casting operation. More specifically, and by way of example, said prior application, Serial No. 1,075, suggests in one embodiment how as many as 427 heat resistant bands or strips can be mounted individually on an equal number of spring-tensioned Winding spools or rolls and guided into the mold cavity for embedding within the ingot as it is being cast. The disclosure of the prior application teaches how the separate bands or strips may be threaded through guide means located above the casting mold in predetermined spaced parallel relation to one another and further how the bottom free ends of the strips can be clamped said predetermined position to a plurality of clamping bars placed on the drop platen which supports the solidified portion of the ingot being cast.

Although very satisfactory results have been obtained utilizing the methods and apparatus for forming hollow or multi-cellular articles according to the teachings of said prior patent applications, it has been found to it volve a rather tedious task. requiring considerable expenditure of human time and relatively skilled labor, to properly mount, guide and tension the individual heat resistant bands so that they are maintained in proper predetermined spaced relation Within the ingot as it is being continuously cast. The same task of threading and mounting the separating strips properly within the mold cavity must, according to said prior application teachings, be duplicated each time it is desired to commence casting a new ingot length.

Generally stated, the principal object of the present invention is to provide an improved method and means for mounting, feeding and guiding a plurality of heat resistant separating strips arranged in predetermined pattern and spaced relation into a mold cavity and into the body of an ingot being continuously cast within said mold cavity. succinctly stated, the present method embraces the concept of mounting a plurality of relatively narrow heat resistant strips in predetermined spaced relation to one another on one or more substantially wider carrier sheets or webs formed of heat destructive or consumable material, and then feeding said one or more carrier sheets with the heat resistant strips mounted thereon into the mold cavity and into the molten ingot being continously cast in the same direction and at the same lineal speed that the ingot is being cast. As will more fully be explained, it is entirely feasible to mount a plurality of the heat resistant strips on a substantial number of individual carrier sheets whereby the heat resistant strips on each carrier sheet are properly arranged in reference to one another and whereby the several carrier sheets may be introduced into the mold cavity and into the ingot in such manner that the heat resistant strips of each carrier are also properly arranged and spaced in reference to the heat resistant strips mounted on all of the other carriers. Thus, for example, in the embodiment of the invention which will hereinafter be described in greater detail, it is disclosed how three or more carrier sheets may be simultaneously fed into the mold cavity and into the molten ingot as it is being cast in such manner that the heat resistant strips mounted on all the carrier sheets extend in spaced parallel pattern, but with the heat resistant strips on each carrier disposed in staggered relation to the heat resistant strips or" each adjacent carrier whereby the ultimate article to be produced will assume the form of a multi-cellular honeycomb struc ture.

The utility and advantage of the present invention over the state of the art as exemplified in said prior enumerated applications may be illustrated by the following comparative example:

As above noted said prior application, Serial No. 1,075, specifically suggests the simultaneous feeding into a continuous casting mold of as many as 427 or more spaced parallel heat separating strips formed of such material as glass cloth, or the like. According to the teaching of said prior application it was required that each individual strip or band be individually threaded through Various guide means in the apparatus to a position of ultimate clamping at the bottom of the mold. In employing the principles of the present invention, and in manufacturing in a product substantially identical to that disclosed in said application, Serial No. 1,075, it is possible to simultaneously cast 427 heat resistant separating strips, for example, by mounting, feeding, and guiding as few as 14 carrier sheets on which have been pre-mounted alternately 30 and 31 individual spaced parallel heat resistant strips. In the example given, not only does the use of only 14 carrier sheets (compared to 427 individual heat resistant strips) reduce the machine set-up time almost 30 fold, but because the heat separating strips may be applied to the carrier sheets by precision equipment in advance of the casting operation, the overall accuracy as concerns the relative spacing of the separating strips is assured and is not nearly so dependent upon the skill and abilities of a machine operator in having to individually thread and clamp some 427 individual strips.

It is believed apparent that numerous other objects and advantages of the present invention will become apparent upon reading the following specification and refer-' ring to the accompanying drawings in which similar characters of reference represents corresponding parts in each of the several views.

FIG. 1 is an isometric view of a section of a relative wide carrier sheet or web on which is mounted a plurality of narrower heat separating strips;

FIG. 2 discloses several of said carrier sheets arranged in juxtaposed position to one another and with the separating strips on each carrier sheet disposed in staggered parallel relation to the. strips on each adjacent sheet; 7

FIG. 3 is a diagrammatic view of a continuous casting apparatus in which a plurality of carrier sheets are mounted on a single feed roll above the mold cavity;

FIG. 4 is a partially diagrammatic view of a clamping block for securing the bottom ends of the carrier sheets inpredetermined spaced relation;

FIG. 5- is a diagrammatic view and side elevation of acastin'gappa'ratus in which the carrier sheets are mounted on separate unwinding reels and are guided into the mold'cavity around a common guide point in the form of a guide roller.

FIG. 6 is? a cross-sectional view of an" ingot showing heat resistant separating; strips embedded therein to define ahoneycomb pattern of cell openings; and i FIG. 7' is an enlarged fragmentary plan view of a honeycom-b section expanded f'rornthe ingot of FIG. 6.

Referring now more specifically to the drawings, FIG. 1' may be considered to illustrate an elongate carrier sheet or webofheat destructible or consumable'material such aspaper, sheet plastic, metal foil, or the like. The term heat destructible as used: throughout the specification and in' the claims is meant to include any suitable'web or' carrier in' sheet form that will either burn. up, melt or otherwise lose its structural integrity or identity upon being subjected to the heat of the casting operation.

FIG. 1 further shows the carrier sheet 1' as having mounted on one surface thereof a plurality of equidis} tantly spaced longitudinally extending parallel heat separating strips or bands 2. As suggested in said prior U.S. applications hereinabove identified, the separating strips 2 may be formed of any suitable material that can withstand the heat. of the casting operation, yet will be capable of mechanical separation from the surrounding ingot material at a later processing stage when it' is desired to expand the body to form a hollow or multi-cellular article. Prior application, Serial No. 704,103, specifically suggests the use of strips of glass cloth, graphite, mineral Wools, asbestos, or similar materials that can withstand the heat of casting and not lose their structural integrity- In accordance with'the present invention, the strips of heat resistant material may be mounted on a carrier sheet by a suitable adhesive, by stitching, or by any other suitable mechanical means. to'the carrier sheets by hand or by any suitable machinery designed for the purpose. The specific means by which the strips 2 are mechanically attached to the sheets 1 and the equipment (if any) used to accomplish this end are considered to be within the skill of the art and do not per se institute a part of the present invention.

FIG. 2 illustrates how a plurality of the carrier sheets with separating bands 2 attached thereto can be juxtaposed in relation to one another whereby the arrangement of the separating strips as embedded in the ingot will function to define a multi-cellular honeycomb pattern. More specifically, as shown in FIG. 2, it is observed how the separating strips 2' onthe middle carrier sheet 1' are disposed staggered, but in parallel, relation to the adjacent top and bottom sheets. As shown in FIGS. 6 and 7, when the separating strips are introduced into the ingot body 8 (FIG. 6) in staggered relation and subsequently expanded (FIG. 7),.a hexagonal cell honeycomb pattern is defined.

Referring to FIG, 3, there. is shown diagrammatically a substantially conventional apparatus as may be em- The strips may be mounted.

ployed for continuously casting ingots from aluminum or alloys of aluminum. More specifically, the apparatus may comprise an open top and bottom mold 3 defining a mold cavity 3a surrounded by a water cooling jacket 4. A drop plate indicated at 6 is mounted for relative movement downwardly away from the bottom of the mold- 3 to permit continuous casting and gradual growth elongation of the ingot. As in conventional practice, it may be. assumed that a pouring spout (not shown) is provided to dispense molten metal through the top of the mold during the casting operation. The drop plate 6 includes a starting piece or plugsection 5 which, at the beginning of the casting operation, is telescoped into the bottom of the mold and permits the initial molten material to solidify before the entire drop plate moves downwardly away from the mold at the speed inwhich: the ingot is: poured and solidified within the mold cavity 3a.

FIG. 3 discloses'how all of. the carrier webs (with the heat-resistant separating strips mounted thereon asaforesaid) may be fed from one unwinding reel. 7 through a slotted guide plate 11 into the mold cavity 3a. The unwinding reel 7 is mounted to revolve about an axle 9, and tension onthe. unwinding reel is maintained. by a friction brakein the form of a leaf spring 16 urged against" a brake drum 16a rotatable withthe reel 7.

The upper guide plate 11, formed with properly oriented and spaced slots functions to maintain the carrier sheets 1 in proper relationship as the sheets are fed downwardly into the top of the mold. In order to secure the bottom extremities of the carrier sheets inproper spaced relation to the drop. plate 6, there may be provided a sectional clamping block structure indicated generally at 12, and constituting a plurality of separable block units, such as indicated at IZci-g in-FIG. 4. The block units l-Za-g may be tightly. clamped in juxtaposed position relative to' one another by means of a through-going rod or shaft 2t threaded at its opposite ends for the reception of tightening nuts 20a disposed withincounter-sunkrecesses- 21 formed in the end blocks 12a and 12g, r'espectively;

The sectional clamping block 12 may be made of thesame size and configuration as the starting piece'or plug 50f the drop block whereby when the sectional clamping block is in use, it effectively functions as the starting piece on which the initial molten material'is initiallycast' to commence forming the ingot.

In operation, as the carrier strips 1 are fed into the upper part of the mold at the same speed that the drop plate 6 moves downwardly, the material from which the carrier sheets 1 is made is consumed or disintegrates upon being subjected to the heat of the molten material Within the mold; whereas, the heat resistant strips 2 are unaffected and thereby become permanently embedded in predetermined spaced relation within the body of the ingot as the latter is continuously formed.

After a desired length of ingot has been formed (perhaps 2-3 meters), the pouring operation is ceased, the ingot is removed entirely from the mold, and the carrier sheets 1 are cut or otherwise separated therefrom. Sub: sequently, the tightening nuts 20a of the sectional clamping block may be unloosenedso as to permit the ingot 8 to be completely removed from the clamping block whereupon operations for casting a new ingot may be reinstituted following the steps hereinabove enumerated.

As is described in some detail'in the prior applications above mentioned, the ingot 8 with the separating strips embedded therein can be passed through a rolling mill in a direction longitudinally and/or transversely of the lengthwise axis of the ingot to attenuate the material in the desired direction and to obtain the desired thicknessf In using glass cloth, for example, as the heat separating strips, the pressure exerted by the rolling mill in attenua ating the metal, will also crushthe glass cloth strips into a powdery substance althoughv leaving. the metal surrounding the glass cloth mechanically separated where: by in subsequent'operations, the rolled'ingot may be sawed or cut transversely into a piece which can be expanded into hollow or multi'cellular bodies by mechanical expansion means well known in the honeycomb art and/or by fluid pressure generated to expand the cells into open condition.

In the embodiment shown in FIG. 3 and where the carrier webs 1 are all mounted on a single unwind roller 7, it is appreciated that the external diameter of the roll will gradually decrease. Thus, the tangential center line at which the material is unwound from the roll (indicated by the reference line R-R) will have a tendency to move inwardly and to the right (of FIG. 3) toward axle 9. This angular change, unless compensated for may have a tendency to create uneven tension along the numerous carrier sheets as they are fed continuously downwardly into the mold casting. If any substantial amount of slack is permitted to form in any of the carrier sheets during the casting process, the same would lead to mist-alignment or this-positioning of the heat resistance strips 2 within the ingot 8 and thereby ultimately result in imperfect cell alignment or configuration in the final product. Therefore, to compensate against lateral shifting of the tangential center line RR' of unwinding, the entire reel assembly may be mounted slidably upon a horizontal frame indicated schematically at 21. By suitable screw adjustment means 22 or equivalent mechanism, the reel assembly may be gradually advanced to the left as unwinding occurs to maintain the tangential center line RR' in fixed location with reference to the vertical center of the mold cavity.

Referring now to FIG. 5 of the drawings, the continuous casting apparatus therein disclosed may be considered as substantially identical to that already specified in reference to FIG. 3. However, the plurality of carrier sheets or webs 1 are shown in FIG. 5 as being each individually supported and unwound from a plurality of unwind reels 13-17, inclusive. In order to maintain the angle at which the carrier strips enter the mold cavity in as much of a straight line path as possible and with relatively small difierences in angle of introduction as between the various carrier strips, there is provided a single and common guide roll 18 of relatively large diameter which defines a common guide point about which all of the carrier strips are guided into position within the upper part of the mold cavity.

In FIG. 5 it is to be expected that the tangential angle at which each of the carrier sheets unwinds from its respective reel 13-17 will also constantly shift to the right as the unwinding from the reel progresses. However, because all of the carrier sheets are guided about a common guide point established by the roller 18, the tangential center line R at which the carrier strips are introduced into the mold cavity will remain constant. Therefore, there is no necessity to have to individually laterally shift the reels 13-17 to the left during the unwinding process as is desirable when using a single unwinding reel for all the carrier sheets as explained in refence to FIG. 3. It is appreciated further that any suitable additional precautions well known in the art of multiple web feeding may be additionally employed to maintain an even tension on all of the carrier webs, such well known means including, butnot being restricted to, various tensioning devices, slack take-up rollers, and other similar mechanisms.

As in the previously described embodiment of FIG. 3, the apparatus of FIG. 5 may be provided with an upper slotted guide plate 11 and a clamping lock unit 12 for securing the lower extremities of the web carriers in proper spaced relation to the drop plate 6.

Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it is understood that certain changes and modifications may be practiced within the spirit of the invention and scope of the appended claims.

I claim:

1. Means for continuously casting an ingot having a known elevated casting temperature with spaced separat ing strips of heat resistant material embedded therein, the combination comprising: a casting mold of the type including an open top and bottom mold cavity with a drop plate vertically aligned and movable downwardly from said mold cavity for supporting the solidified bottom portion of the ingot as it is continuously cast; at least one carrier web made of a sheet material that will be consumed by the heat of the molten casting at its elevated casting temperat re; a plurality of separating strips each substantially narrower than the width of the carrier and made from a material that will withstand the elevated casting temperature of the molten casting; said separating strips mounted on said carrier web extending in a direction substantially parallel to the vertical axis of said mold cavity and arranged in predetermined horizontally spaced relation to one another; and means located above said mold cavity for feeding and guiding said carrier web into said mold cavity at substantially the same speed and in the same direction as the speed and direction of continuous casting of the ingot.

2. The combination of claim 1 and wherein said last named means comprises a single unwinding reel mounted above said mold cavity and on which is spirally wound all of said carrier webs; and means for adjustably laterally shifting the axis of rotation of said reel to compensate for progressive decrease in the external diameter of said reel as unwinding of the carrier Webs therefrom progresses and to maintain the tangential center line of unwinding from the reel in relatively fixed vertical all ment in reference to said mold cavity.

3. The combination of claim 2 and wherein said last named means for feeding and guiding said carrier webs into said mold cavity comprises a plurality of unwinding reels on each of which is spirally wound one or" said carrier webs; all of said reels located above said mold cavity; and a fixed guide point disposed in vertical alignment above said mold cavity between said reels and said cavity; all of the carrier webs fed from said reels being guided about said fixed guide point at a constant angle of entrance into said mold cavity.

4. The combination of claim 3 and wherein said fixed common guide point comprises a guide roller in which one portion of its periphery functions as the common guide point, the tangent to which is disposed in center vertical alignment with said mold cavity.

5. In the art of casting an ingot at a predetermined elevated casting temperature the steps comprising: providing at least one carrier web made of a sheet material that will be consumed at said predetermined elevated casting temperature; providing a plurality of separating strips each of substantially narrower width than the carrier web and made of a material that will withstand the heat of said predetermined casting temperature; mounting said plurality of strips on said carrier web in horizontal spaced relation relative to each other; continually casting an ingot into a vertically disposed mold cavity and simultaneously feeding said carrier and strips mounted thereon downwardly into said mold, thereby permitting the em bedding of said Web mounted strips in the desired position in the ingot without the necessity of individually guiding each individual strip to its appointed position and also causing the carrier sheet to disintegrate and lose its structural identity under the influence of the casting heat.

6. The method of claim 5 and which includes the steps of providing a plurality of said carrier webs and mounting on each web a plurality of said strips, and feeding simultaneously said plurality of carrier webs and strips mounted thereon into the mold cavity with the strips on alternate carriers disposed in staggered and parallel relationship to one another whereby the cast ingot may be expanded to form a honeycomb pattern of cell openings 7 8 r defined byrthe spaces previously occupied by the separat- 2,950,512; Wilkins Aug. 30, 196.0 ing strips. 3,010,200 Wilkins Nov. 28, 1961. 7 3,016,587 Brick L.; 'Jan. 16', 1962' References Cited in the file of this patent 7 3,055,067. R th Sept; 25, 1962? UNITED STATES PATENTS 5 FOREIGN PATENTS I $3? $12,953 Great Britain Sept; 29, 1939 traus et ec.

2,117,455 Sandler May 17,1938 OTHER REFERENCES 2,608,502 'Merr'iman' Aug. 26, 1 952 10 WebstergNew International Dictionary, 211d editio 2,803,343 Shrdyer Aug; 15, 1958 Unabridged; 1940, published by G; aiid'C; Merriam-Cq.

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1. MEANS FOR CONTINUOUSLY CASTING AN INGOT HAVING A KNOWN ELEVATED CASTING TEMPERATURE WITH SPACED SEPARATING STRIPS OF HEAT RESISTANT MATERIAL EMBEDDED THEREIN, THE COMBINATION COMPRISING: A CASTING MOLD OF THE TYPE INCLUDING AN OPEN TOP AND BOTTOM MOLD CAVITY WITH A DROP PLATE VERTICALLY ALIGNED AND MOVABLE DOWNWARDLY FROM SAID MOLD CAVITY FOR SUPPORTING THE SOLIDIFIED BOTTOM PORTION OF THE INGOT AS IT IS CONTINUOUSLY CAST; AT LEAST ONE CARRIER WEB MADE OF A SHEET MATERIAL THAT WILL BE CONSUMED BY THE HEAT OF THE MOLTEN CASTING AT ITS ELEVATED CASTING TEMPERATURE; A PLURALITY OF SEPARATING STRIPS EACH SUBSTANTIALLY NARROWER THAN THE WIDTH OF THE CARRIER AND MADE FROM A MATERIAL THAT WILL WITHSTAND THE ELEVATED CASTING TEMPERATURE OF THE MOLTEN CASTING; SAID SEPARATING STRIPS MOUNTED ON SAID CARRIER WEB EXTENDING IN A DIRECTION SUBSTANTIALLY PARALLEL TO THE VERTICAL AXIS OF SAID MOLD CAVITY AND ARRANGED IN PREDETERMINED HORIZONTALLY SPACED RELATION TO ONE ANOTHER; AND MEANS LOCATED ABOVE SAID MOLD CAVITY FOR FEEDING AND GUIDING SAID CARRIER WEB INTO SAID MOLD CAVITY AT SUBSTANTIALLY THE SAME SPEED AND IN THE SAME DIRECTION AS THE SPEED AND DIRECTION OF CONTINUOUS CASTING OF THE INGOT. 